The start of an inquest into the Sydney cafe siege has heard that hostage Katrina Dawson was killed by fragments from a police bullet or bullets.

Another hostage, cafe manager Tori Johnson, was killed by a bullet to the head from gunman Man Haron Monis. His death prompted police to storm the Lindt Chocolate Cafe and kill Monis.

The inquest aims to establish whether deaths were avoidable and if it should have been treated as a terrorist event.

Eighteen people were taken hostage.

The stand-off at the cafe in Martin Place in Sydney's business district on 15 December led to a massive police operation and the shutdown of a large part of the city centre.

At the opening of the coroner's inquest in Sydney, Jeremy Gormly, the lawyer assisting the state coroner, said Ms Dawson was "struck by six fragments of a police bullet or bullets which ricocheted from hard surfaces into her body".

Media captionLawyer Jeremy Gormly: "Ms Dawson was struck by six fragments of a police bullet or bullets"

"I will not detail the damage done to Ms Dawson other than to say that one fragment struck a major blood vessel. She lost consciousness quickly and died shortly afterwards."

Australian media reports earlier this month had indicated that Ms Dawson, a 38-year-old barrister and mother of three young children, had died after being hit in the heart and shoulder by fragments from a police bullet.

Bomb claim

The inquest heard that Monis entered the cafe on the morning of 15 December with a sawn-off shotgun hidden in a plastic bag.

He ordered chocolate cake and tea, and asked to speak to the manager, Mr Johnson. After ordering Mr Johnson to lock the cafe, he announced: "This is an attack. I have a bomb."

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Police entered the cafe after one of the hostages was shot dead, the inquest heard

He ordered the cafe manager to say that Australia was under attack from Islamic State militants and that Monis had planted radio-controlled bombs around the busy Sydney tourist precinct, Circular Quay, and Martin Place - none of which was true.

What the inquest wants to know

How Tori Johnson and Katrina Dawson were killed

How police managed the siege, and what protocols they used, and how they managed hostages and the families during and after the siege

Details of Monis's political associations and public activity, his religious claims, his criminal history, his media profile and his personal relationships

How Monis was out on bail, particularly over the charges concerning the murder of his ex-wife.

A number of hostages managed to escape as the siege went on, then at 02:00 local time on 16 December, special police stormed the cafe after a police marksman saw Monis shoot the kneeling Mr Johnson in the back of the head.

Earlier unconfirmed reports in the Australian press had said Mr Johnson was shot while trying to disarm Monis, but this was not mentioned by the coronial report.

The inquest heard that Monis was killed instantly when police entered the cafe. At least two police bullets hit him in the head and 11 other bullets or fragments struck his body. The police used stun grenades, known as flash bangs, as they went in.

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Man Haron Monis was facing a range of criminal charges at the time of the siege

Monis fired five shots during the entire siege, the inquest heard.

The first shot was directed at hostages as they fled the scene. He then shot Mr Johnson. The other bullets were fired when police stormed the cafe. Monis was later found to have had 21 more cartridges in his pocket.

'Horrifying events'

Monis, who came to Australia as a refugee from Iran, had a history of religious activism and was on bail at the time of the siege for dozens of sexual assault charges and for being an accessory to the murder of his ex-wife.

He claimed to be a cleric and asked his hostages to display an Islamic flag during the siege. However, questions remain about whether he had any links to international militant networks.

His partner Amirah Droudis, who is also facing murder charges over his ex-wife, will be represented at the inquest.

Image copyrightReutersImage caption
People were evacuated from buildings nearby as the siege brought parts of central Sydney to a standstill

"Rarely have such horrifying events unfolded so publicly," New South Wales coroner Michael Barnes told the court. "These events have precipitated an outpouring of emotion, anguish, anger, resentment and despair."

Outside court, one of the surviving hostages, 82-year-old John O'Brien said: "It's been very upsetting for Tori Johnson's family."

Six of Mr Johnson's family members attended the session. None of Ms Dawson's family were present.

The inquest has now adjourned. A date has yet to be announced for the next hearing. All the surviving hostages are expected to give evidence.

Meanwhile other investigations into the siege are continuing, including a joint federal and New South Wales state government review of why Monis was given asylum and eventually citizenship in Australia and why he was granted bail in 2013.

How the 16-hour Sydney siege unfolded

1. At 09:45 on Monday local time (22:45 GMT Sunday) police are called to the Lindt Chocolat Cafe in Sydney following reports of an armed robbery. It soon emerges a gunman is holding a number of people hostage.

2. Between 16:00-17:00, three men, then two women, sprint to safety from the cafe's side door - a fire exit.

3. Just after 02:00 on Tuesday, a loud bang is heard from the cafe and special operations officers advance towards the side door.

4. More hostages escape, running to safety on Elizabeth Street.

5. Moments later, commandos storm the cafe via a number of entrances. The remaining hostages escape.

6. Police officially confirm the end of the siege at 02:45 local time. They later report the deaths of three people, including the gunman.